Cyber crooks are getting smarter, more inventive and diversifying their attack portfolios, security expert McAfee said in a newly released threat report for Q4 2017 that tracks malware, ransomware and other security menaces during the period.

Among the contributing factors to a substantial rise in cyber hacking frequency and severity is a spike in cryptocurrency value during Q4 2017, which attracted cyber criminals like hornets to a nest. As expected, McAfee’s data showed there’s a lot of gloom out there:

McAfee said it counted 222 publicly disclosed security incidents in Q4, a 15 percent decrease from the prior quarter. Some 30 percent of all revealed Q4 hacks took place in the Americas, followed by 14 percent in Europe and 11 percent in Asia.

As the world has become more digitized, cyber criminals have followed suit, taking advantage of crime becoming easier to execute, less risky and more profitable, said Steve Grobman, McAfee chief technology officer. For example, as Bitcoin rushed upwards in value, cyber crooks branched out from old reliables such as ransomware to embrace hijacking cryptocurrency.

More to the point, McAfee researchers discovered Android apps developed exclusively for the purpose of cryptocurrency mining. And, fileless malware leveraging Microsoft PowerShell, has become e a go-to toolbox for cyber crooks. “It should be no surprise to see criminals focusing on stealthy fileless PowerShell attacks, low risk routes to cash through cryptocurrency mining, and attacks on soft targets such as hospitals,” said Grobman.

The McAfee report also drilled down on the particular markets and methods favored by bad actors. With healthcare, the researchers concluded that organizational failure to comply with security best practices or fix known software vulnerabilities contributed to the high number of incidents.